Their are 2 great Christian-focus national sororities:
Phi Beta Chi with 11 chapters/colonies
Alpha Delta Chi with 8 chapters/colonies
Unfortunately, since the sororities do not have 12 chapters yet, they are not eligible for NPC associate membership. If you would like to contact them, please PM me and I can send you a contact name and email.
Edited to add:
Phi Beta Chi national web site:
www.phibetachi.org
Alpha Delta Chi's national web site is being updated, but a good chapter web site:
www.alphadeltachi.net